1. Field of the Invention
This invention relates to an oil supplying structure for a gear shaft bearing of a transmission for a vehicle and, more particularly, to a structure which can improve lubrication by stably supplying oil scattered by a rotation of a differential gear to each gear shaft bearing.
2. Description of the Conventional Art
In general, a transmission for a vehicle provides the mechanical advantage that enables the engine to propel the vehicle under various loads. It also furnishes the driver with a selection of vehicle speeds while the engine is held at speeds within the effective torque range. The purpose of the transmission is to provide the operator with a selection of gear ratio between engine and wheels so that the vehicle can operate at an optimal efficiency under a variety of driving conditions and loads, to provide reverse, and to allow engine braking.
The transmission comprises a transmission housing containing input and output shafts on which a plurality of gears are disposed. In case of front-wheel drive vehicles, a differential gear and a final reduction gear are integrally formed at an end of the output shaft.
In the transmission described above, to support the input and output shafts, a supporting boss 100 is formed on the inside surface of the housing and the shafts are rotatably supported on each rolling bearing interposed in fixing holes each formed on the supporting boss. Oil should be sufficiently supplied to the rolling bearings in order to minimize power loss by reducing the friction drag and to prevent the abrasion of the rolling bearing.
However, when supporting the input and output shafts to the housing, it is conventional up to now that bearings 103 and 104 are inserted in respective fixing holes 101 and 102 and the input and output shafts 105 and 106 are supported on the respective rolling bearings 103 and 104 as shown in FIG. 5.
Accordingly, the oil filled up in the housing with predetermined oil level is sufficiently supplied for each portion of the gears but is not sufficiently supplied for the bearings inserted in the fixing holes of the supporting boss such that friction drag of the bearings increases and the abrasion of the bearings as well as power loss is extreme.